With the increaseing global demand for energy, we are facing a huge challenge of energy sustainability. Renewable energy has attracted an immense amount of interest with regard to solving the sustainbility issue. Among the various renewable energy sources, solar heat and waste heat energy has significant advantages due to its availability. Thermoelectric nanomaterials play an indispensable role in heat-to-electricity energy conversion. A high energy conversion efficiency is critical for practical applications of thermoelectric energy conversion systems, and understanding the fundamentals of energy conversion mechanisms is essential. This book details thermoelectric energy conversion nanomaterials and the related manufacturing processes. It also introduces the latest research progress in thermoelectric energy conversion nanomaterials. It is a great reference for readers from both academia and industry.